Custom Device Targets

In addition to automatic hardware discovery, fparted allows power users and developers to attach custom block device targets (such as loopback image mounts, external SCSI controllers, or network block devices).

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🎯 Adding a Custom Device

Users can invoke the Add Custom Device action via the Navigation Rail or the keyboard shortcut Ctrl+N / Cmd+N.

Validation Preconditions

Before adding a device target to the active list, fparted performs preflight checks: 1. Device Existence: Verifies that the path exists in the filesystem and represents a valid block device or raw disk image. 2. Canonical Resolution: Resolves symlinks (e.g., /dev/block/bootdevice/by-name/... to /dev/block/mmcblk0p...). 3. Partition-to-Base Mapping: If the user inputs a partition node (/dev/block/sda1), fparted resolves the parent disk node (/dev/block/sda) and loads the entire disk structure. 4. Duplicate Prevention: Rejects paths that are already loaded in the active session. 5. Geometry Probing: Probes sector size and capacity before creating the UI entry.

sequenceDiagram
    participant User
    participant Dialog as Add Device Dialog
    participant Probe as Storage Probe
    participant State as Application State

    User->>Dialog: Enters "/dev/block/loop0"
    Dialog->>Probe: Verify block device & probe geometry
    Probe->>Probe: Query parted & blkid
    alt Valid Block Target
        Probe-->>Dialog: Return Disk model
        Dialog->>State: Add to loaded disks list & select
        Dialog->>User: Close dialog & navigate to new disk
    else Invalid Target or Probe Failure
        Probe-->>Dialog: Error (e.g. permission denied or invalid geometry)
        Dialog->>User: Display actionable error message
    end